Radio electrician&#39;s and power transmission safe test device



G.-A. THOMAS 2,969,519

RADIO ELECTRICIAN'S AND POWER TRANSMISSION SAFE TEST DEVICE Jan. 24, 1961 Filed June 24, 1958 6 m m T M W 2 m NL. IT T @A v a m V. 1 M m y 6 2 Ema/Q?! C a a. F

m P. v 1 5 HHHHI AV iilvlll lra? United States Patent RADIO ELECTRICIANS AND POWER TRANSMIS- SION SAFE TEST DEVICE Gitchel A. Thomas, 3703 Moore St., Los Angeles, Calif.

Filed June 24, 1958, Ser. No. 744,170

3 Claims. (Cl; 339-33) This invention relates to safety devices, to be used by various types of workers in the electrical field. Such workers might be, for example, electricians, linemen, and various types of radio and radar technicians.

The main object of the safety device constituting the present invention is to provide a tool of the test prod type, by means of which one may hook onto or into an electrical circuit to test, connect, or short out said circuit without any danger of endangering the life or health of the operator using the same, and without the necessity of shutting off the current flowing within the circuit.

A more specific object of the connector device comprising the present invention is to provide adjustable means adapted with maximum ease and speed to accommodate a wire or plate which is to be connected to the extremity of the safety device and which is to be moved with said device to make the examination of different circuits or parts whereby to test the same, with the construction being such that the wire or plate or other surface will be automatically gripped when the plunger is released, with said plunger being readily accessible to the thumb or the hand of the user of the device.

Another object is to provide a safety device of the character stated which will be of simple construction, will be inexpensive to manufacture, will be capable of use with maximum ease, and will be eflicient in operation.

Other objects will appear from the following description, the claims appended thereto, and from the annexed drawing in which like reference characters designate like parts throughout the several views and wherein:

Figure l is a side elevational View of the device according to the present invention, a conductor to which the device is hooked being illustrated fragmentarily and in dotted lines;

Figure 2 is a longitudinal sectional view substantially on line 2-2 of Figure 1;

Figure 3 is a bottom plan view of the device, the conductor being shown in dotted lines;

Figure 4 is a transverse sectional view, substantially on line 4-4 of Figure 2;

Figure 5 is a fragmentary side elevational view of the device, showing the same engaged with a plate-like terminal;

Figure 6 is a fragmentary view in side elevation of a modified form;

Figure 7 is a fragmentary side elevational view of the modification shown in Figure 6, as seen from the left of Figure 6; and

Figure 8 is a view similar to Figure 7, showing another modification.

Referring to the drawing in detail, designated at 10 is an elongated, constant-diameter, cylindrical sleeve formed of electrical insulation material, and having at its outer end external threads 11. Snugly engaged in the inner end of sleeve 16, that is, the end that is disposed nearer the work, is a plug 12 of elongated, cylindrical, solid formation, also formed of electrical insulation material 2,969,519 Patented Jan. 24, 1961 "ice and having an outer end portion 13 projecting exteriorly of the sleeve and formed with a tapered distal end 14. Plug 12 is fixedly secured within the sleeve by means of a set screw 16 which extends to an opening of the sleeve and which is threadedly engaged in a radial, threaded recess of the plug.

A cap 18, also of electrical insulation material, has an end wall 19 formed with a large center opening 20. Cap 18 has a cylindrical side wall which, at the end thereof remote from the end wall 19, is reduced in thickness as at 22 and internally threaded for engagement with the threads 11.

An elongated, cylindrical plunger 23 is formed intermediate its ends with a circumferential collar 24, against which abuts a large diameter, small, compression coil spring 26 circumposed about the plunger and hearing, at its other end, against a washer 28 also circumposed about the plunger.

The plunger projects through opening 20, being slidable in said opening, and under the bias of the spring 26 is resiliently, yieldably shifted in a direction outwardly of the sleeve. The projecting portion of the plunger is coaxially aligned with and is connected to a plunger head 30 the distal end 31 of which is of increased diameter, constituting means depressible by the thumb of a users hand.

Head 30, at its inner end, has an axial boss 32 externally threaded and formed with a recess 33. Boss 32 is engaged in a threaded recess 35, formed in the projecting end of the plunger 23.

An elongated, straight rod 34 of electrically conductive material extends in parallel, closely spaced relation to the longitudinal median lines of the plunger 23 and plug 12. Rod 34 is fixedly secured within the plunger, having at one end a lateral extension engaged by the head of a screw 36 threadedly connected to the plunger within the recess 33 (Figure 2).

Rod 34 extends through a small, flared grommet 38 that is fixedly mounted in the inner end of the plug 12, and which also extends through a flared grommet 40 similarly mounted in the inner end of the plunger 23. Rod 34, at the end thereof remote from the screw 36, has a hooked portion 42, and fixedly secured to said hooked portion is a sharpened, triangular point 44.

Designated at 46 is a small, conductive contact plate, which is fixedly secured to the tapered end 14 of the plug 12 in confronting relation to the hook 42. The rod 34 is slidable in an elongated, longitudinal bore 47 formed in the plug 12, and accordingly, in use of the device, one may bring the hook 42 into proximity to an electrical cable 48, after which the thumb of the hand grasping the sleeve 10 is used to depress the plunger. This shifts the book 42 away from the contact plate 46, to provide sufiicient space therebetween for entry of the cable 48. On release of the plunger, spring 26 is free to expand, thus shifting the plunger 23 in a direction axially outwardly of the sleeve 10, that is, away from the cable 48. The hook 42 thus moves toward the contact plate 46, causing the cable 48 to be tightly gripped between the contact plate and the hook. An electrical connection is thus made between the contact plate and the cable.

A wire or lead 50 is covered with insulation, and is extended through an obliquely disposed opening 51 formed in the sleeve 10. Within the sleeve, in the space between the plunger 23 and the plug 12, the wire 50 is bared and is connected to a straight, electrically conductive wire 52, which is embedded in the plug and which is secured to the contact plate 46.

By reason of this arrangement, it will be seen that with the cable 48 engaged against the contact plate 46, an electrical connection is made between the cable and wire 50,

for test purposes, or for the purpose of connecting or shorting out anelectrical circuit in which the cable 48 is included, without endangering the life or health of the operator and without shutting off the electrical current.

In some instances, it may be desired to merely apply the device as a prod, and in such cases, the point 4-4 would be used. When the device is used in this manner, one merely applies the test point 44 to the electrical component or circuit that is to be tested, without hooking it to said component or circuit.

In some instances, the terminal or contact with which an electrical connection is to be made is of fiat stock. This is shown at 54 in Figure 5. In such an instance, one depresses the plunger 23 in the manner previously described, sufiiciently to provide a space between contact plate 46 and hook 42 large enough for entry of the fiat member 54. On release of the plunger, the member 54 will be clamped between the contact plate 46 and the hook 42, and an electrical connection between the member 54 and the wire 50 is made in the same manner as previously described herein.

In Figures 6 and 7, there is shown a modified construction, which is identical in all respects to that shown in Figure 2, with the exception of the work-engaging end portion of the rod 34. In this form of the invention, said portion, designated at 56, is a triangularly shaped member tapering to a sharp point adapted to be placed in contact with any of the various electrical components, not shown, that are to be probed. At the base of the triangularly shaped test point, there is formed a flat surface, which is wider than the thickness of the rod 34 so as to define at opposite sides of the rod shoulders 57 (see Figure 6). Said surface, which has been designated at 58, extends laterally in one direction from the rod (Figure 7) in confronting relation to the plate 46, so as to cooperate with said plate in defining a clamp means in which the conductor 48 or the member 54 can be pp In the form of the invention shown in Figure 8, the rod 34 is connected at 68 to one of the apices of a sub stantially open triangular test point 62 having a side 64 thereof disposed in spaced confronting and substantially parallel relationship with respect to the contact plate 46. From the side 64 and intermediate the ends thereof projects an inverted substantially V-shaped element 66, This particular form has also been found desirable in meeting certain specific uses.

It is believed apparent that the invention is not necessarily confined to the specific use or uses thereof described above since it may be utilized for any purpose to which it may be suited. Nor is the invention to be necessarily limited to the specific construction illustrated and described, since such construction is only intended to be illustrative of the principles, it being considered that the invention comprehends any minor change in construction that may be permitted within the scope of the appended claims.

What is claimed is:

1. A combined electrical test probe and connector device comprising: a sleeve of electrical insulation material formed open at its opposite ends; a solidly constituted plug also formed of an electrically insulative material and fixedly mounted in one end of the sleeve, the plug having one end projecting out of the sleeve and formed with a fiat end surface; a flat, electrically conductive plate overlying and fixedly secured to said end surface, said plate having a marginal notch; an electrically conductive connector wire embedded in and extending from end to end of the plug, one end of the wire being secured to said plate; a lead secured to the other end of said wire and projecting laterally outwardly from the sleeve; an electrically insulative plunger slidably engaged in and projecting out of the other end of the sleeve; spring means interposed between the sleeve and the plunger and stressed to bias the plunger in a direction away from the plug to a normally extended position; a plunger head secured to the projecting portion of the plunger for shifting the same in an opposite direction against the force of said spring; and a rod of electrically conductive material having one end anchored to the plunger between the plunger and the plunger head, said rod extending within the plunger and being slidably engaged in the plug in spaced, parallel relation to the longitudinal median line of the plug, the rod at its other end including a generally triangular point projecting away from said plug, said rod extending through the notch out of contact with the plate and being formed at the base of said point with a surface extending laterally of the rod in one direction across the longitudinal median line of the plug, said surface being in confronting relation to the plate so as to constitute a clamp means in cooperation therewith when the device is in use as an electrical connector, said surface of the rod being engaged directly against the plate when the device is in use as a probe.

2. A combined electrical test probe and connector device as in claim 1 wherein said surface is wholly fiat and parallel to the plate, said surface being greater in width than the thickness of the rod so as to define at opposite sides of the rod a pair of shoulders against which an electrical conductor may be engaged when the plate and said surface are in use as a clamp means.

3. A combined electrical test probe and connector device comprising a sleeve of electn'cal insulation material formed open at its opposite ends; a solidly constituted plug also formed of an electrically insulative material and fixedly mounted in one end of the sleeve, the plug having one end projecting out of the sleeve and formed with a fiat end surface; a flat, electrically conductive plate overlying and fixedly secured to said end surface, said plate having a marginal notch; an electrically conductive connector wire embedded in and extending from end-toend of the plug, one end of the wire being secured to said plate; a lead secured to the other end of said wire and projecting laterally outwardly from the sleeve; an electrically insulative plunger slidably engaged in and projecting out of the other end of the sleeve; spring means interposed between the sleeve and the plunger and stressed to bias the plunger in a direction away from the plug to a normally extended position; a plunger head secured to the projecting portion of the plunger for shifting the same in an opposite direction against the force of said spring; and a rod of electrically conductive material having one end anchored to the plunger between the plunger and the plunger head, said rod extending within the plunger and being slidably engaged in the plug in spaced, parallel relation to the longitudinal median line of the plug, the rod at its other end being formed-with a surface extending laterally of the rod in one direction across the longitudinal median line of the plug, said surface being in confronting relation to the plate so as to constitute a clamp means in cooperation therewith when the device is in use as an electrical connector, said surface of the rod being engaged directly against the plate when the device is in use as a probe.

References (Zited in the file of this patent UNITED STATES PATENTS 2,516,657 Spendlove July 25, 1950 2,529,270 Webster Nov. 7, 1950 2,654,075 Gaborc Sept. 29, 1953 2,677,117 Swain Apr. 27, 1954 2,682,649 Blonder June 29, 1954 FOREIGN PATENTS 748,811 Great Britain May 9, 1956 

